Sitting Devoe for Cole makes no sense which is basically the line up you suggested. We would be significantly worse off on offense, and we'd be worse off defensively because of Cole having to guard the 3. That'd be true even with Devoe instead of Bubba, but it just is made worse considering Bubba has been a target on defense. But even if Cole is the one getting minuets at the 3, that doesn't really change the issue. It'd just be playing him more than Bubba or Usher and we'd still have issues with depth. Also, offensively, because Cole isn't a threat at all from the outside, either shot or off the dribble, and we'd have Banks and Moses already down inside trying to get position. I also disagree with defense being better at all much less tremendously. Cole is not an overly strong defender, and certainly moreso at the 3. Even in zones he is slow on his rotations when put on the wing,
And in general I have never quite understood a lot of the hype surrounding Cole. He was touted as being more polished than Moses but that wasn't really the case and he's pretty much the same player he was as a freshman.
But giving us what Usher gives us isn't a good thing unless they are replacing Usher. Because replacing any of the other starters with Usher level production is a serious downgrade. And what you're suggesting is either having multiple of those 4 out at a time, or basically keeping one on the bench most of the time. Sure that will lead to being fresher at the end of games, and it'll mean we are behind more unless we magically don't get worse when playing worse players. What is easy is making vague comments about players being able to play x minutes and not having to actually account of the loss of who comes out when they come in. Saying Cole/Moore can give us 10 minutes a game is fine. But there is a large difference between them getting 10 minutes at the 3 in exchange of Bubba/Usher, and 10 minutes in exchange for Banks/Wright/Devoe.
To put it another way, anytime Jose, Mike, Moses, or James comes off the court we are fielding a significantly worse line up. And since we aren't building leads that we can use as buffer we can't really afford to put out lineups that are significantly worse.